Prestack depth migration by controlled illumination is an efficient migration technique oriented to target structures. It can improve the image equality of the target zone by controlling the directional characteristics of the incident source wavefield at the target. The key point is to construct the synthesis operators for array shot records, and they are usually obtained by inversely extrapolating the predefined source wavefield at the target upward to the surface. We introduce the surface controlled illumination which performs the control of source wavefield illumination at target with the synthesis operators to be constructed by quick rotations of a kernel synthesis operator directly at surface. It is very efficient as well as advantageous to achieve the high-quality image of the complex structures. Here, we further propose the multi-target surface controlled illumination scheme. It controls source wavefield illuminations of multiple targets to obtain the fine image of the whole structure with the targets selected depending on the complexity of the medium. The Marmousi data are migrated to demonstrate this technique and some comparisons are made with the migration of conventional shot gathers and plane wave. The results show that, for the complex structure with steep dipping reflectors and abrupt lateral velocity variations, control over only few targets can greatly improve the image of the whole profile so that the fine imaging of the whole profile is performed while the migration with high efficiency is resulted.
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